How can we effectively manage data that changes over time? This research proposes a data model and query language for handling time-dependent geometries, especially those describing moving objects in spatio-temporal databases. The work introduces two fundamental abstractions: moving point and moving region, representing objects' time-dependent position and extent. These are presented as attribute data types with suitable operations, extending DBMS capabilities. The design emphasizes orthogonality, genericity, consistency of operations, and closure between non-temporal and temporal types. This abstract data type extension offers a powerful and expressive system for querying spatio-temporal data, including moving objects. By formally defining types and operations, the paper provides a precise foundation for implementing a spatio-temporal DBMS extension, enabling more sophisticated data management and analysis.
Published in ACM Transactions on Database Systems, this study aligns with the journal's focus on database theory and design. By proposing a data model and query language for representing and querying moving objects, the paper contributes to the advancement of database management systems and their ability to handle spatio-temporal data, reflecting the journal's core interests.